What describes demand response in power systems?

• A. Increases demand during peak hours.
• B. Shifts or reduces consumption in response to price signals or grid conditions to ease variability and improve reliability.
• C. Eliminates the need for energy storage.
• D. Only measures consumer electricity usage.

Answer: (B)

Demand response means customers adjust when and how much electricity they use in reaction to price signals or grid conditions. The goal is to reduce or shift demand during times of high price, tight supply, or grid stress, which helps smooth out variability from variable renewables and keeps the system reliable. It’s about action—curbing or shifting load—rather than just consuming or measuring energy.

That’s why this description fits best: it explicitly describes reducing or shifting consumption in response to signals or conditions to ease variability and improve reliability. The other options don’t fit because they imply increasing demand, removing the need for storage, or only measuring usage, none of which capture the responsive, action-based nature of demand response.